Vapor generating apparatus



1967 e. A. PATTERSON 3,

VAPOR 3 ENERATI NG APPARATUS Filed Aug. 19, 1965 2 Sheets-Sheet iINVENTOR. Gordon A. Parferson ATTORNEY 12, 1967 G. A. PATTERSON 3,

VAPOR GENERATING APPARATUS Filed Aug. 19, 1965 2 Sheets-$heet UnitedStates Patent 3,357,408 VAPOR GENERATING APPARATUS Gordon A. Patterson,North Canton, Ohio, assignor to The Babcock & Wilcox Company, New York,N.Y., a corporation of New Jersey Filed Aug. 19, 1965, Ser. No. 430,9069 Claims. (Cl. 122-6) ABSTRACT OF THE DISCLOSURE A reinforcingarrangement for a tubulous wall in a vapor generator, which provides areinforcing member that extends lengthwise across the wall and betweenpairs of lugs mounted to the wall, and is retained, by lock membersreceived by the lugs, in a position for abutting contact with the wallto reinforce it is directions perpendicular to its plane, the lugs andlock members being positioned to allow free relative movement betweenthe wall and reinforcing member in directions parallel to the lengththereof.

This invention relates to vapor generating apparatus, especially thoseof the kind having tubulous walls forming part of a furnace chamber andbuckstay structure for reinforcing the walls, and more particularly toimproved means for connecting the buckstays to the walls.

In conventional buckstay structure of the type set forth a horizontaltie bar supported by an I-beam engages the wall to be braced. The tiebar is held against the outer surface of the wall by pairs of L-shapedclips which are field welded to the wall at horizontally spacedlocations along the length of the bar after the latter is positioned.The clips of the conventional structure define with the wall surface ahorizontal series of C-shaped retaining devices for connecting the tiebar and the wall, while permitting differential expansive movement ofthe wall relative to the tie bar. The novel structure of the presentinvention serves the same purpose, but accomplishes it more simply andmore economically by eliminating welding at the assembly site through anarrangement which lends itself to almost complete prefabrication of thewall and the buckstay subassemblies. As a result, it is only necessaryto connect the tie bar to the wall by the manual insertion of dowels orpins at the construction site.

According to the present invention the tie bar is connected to atu-bulous wall by means of lugs and a locking element at each of anumber of spaced locations along the length of the bar. At each locationwhere a connection is to be made the horizontal tie bar is receivedbetween vertically spaced lugs, each of which has a bight portionprojecting horizontally from the wall to receive a manually insertablelocking element. The lugs and locking element cooperate to secure thetie bar to the wall.

More specifically, the lugs are preferably U-shaped and preassembledwith the wall, the upper and lower lugs being associated in pairs athorizontally spaced locations across the width of the wall toaccommodate the tie bar between them. The tie bar is preassembled withan I-beam by being rigidly connected thereto at horizontally spacedlocations along the length of the buckstay structure. Final assembly atthe construction site involves aligning the tie bar between theassociated pairs of lugs and inserting a pin through each pair of lugsto hold the tie 3,357,408 Patented Dec. 12, 1967 bar against lateralmovement, e.g., away from the wall. However, the connection between thetie bar and the wall does not interfere with thermal expansion of thewall across its entire width and height.

The various objects, features and advantages of the invention willappear more fully from the detailed description which follows, taken inconnection in the accompanying drawings forming in the part of thepresent invention, and in which:

FIG. 1 is a partial sectional plan view of a fluid cooled combustionchamber incorporating the novel buckstay in accordance with thisinvention.

FIG. 2 is a vertical sectional view of the connection between the walland the buckstay, taken along lines 2 2 of FIG. 1, and shown on agreatly enlarged scale.

FIG. 3 is a plan view of the connecting structure shown in FIG. 2.

FIG. 4 is a fragmentary perspective vie-w of assembled apparatusincorporating the present invention, taken at a corner thereof.

FIG. 5 is a horizontal sectional view of modified tubulous wallstructure for use on the present invention, shown on an enlarged scale.

FIG. 6 is an elevational view of the structure of FIG. 5.

FIG. 7 is a. vertical sectional view taken along line 77 of FIG. 5.

As shown in the drawings, the illustrated wall construction includes aplurality of wall panels 10 comprising closely spaced upright tubes 12and intermediate membrane bars 13, joined together to define a furnacechamber 14 for containing hot products of combustion which come intoheat transfer relationship with the inner surfaces of the tubes 12. Theupper and lower ends of the tubes 12 are connected into a fluidcirculation system (not shown). Intermediate the ends of the tubes 12,which may be of considerable extent in some installations, appropriatelyvertically spaced, horizontally extending tie bars 16 hold the tubes intheir preassembled operative relationship to one another, bracing thepanels 10 against pressure forces, and in effect forming a band aroundthe periphery of the chamber 14 just as the straps of a keg.

There are one or more tie bars 16 associated with each wall panel 10.Each tie bar 16 is rigidly connected to a reinforcing buckstay 18consisting of'a' relatively large, horizontally disposed, I-beam. It isthe function of the buckstay assembly to prevent buckling of the tubularwall which may occur under any operating conditions, while at the sametime permitting relative expansion and contraction of the wall 10because of their differences in operating temperature. The connectionbetween each tie bar 16 and its associated buckstay 18 is effected atspaced locations along their length by means of buckstay brackets 20welded or otherwise joined to the inner flange thereof and standoff lugs22. The latter extend horizontally between the tie bar 16 and thebuckstay brackets 20 and are joined thereto as by welding to maintainthe tie bar 16 in rigidly spaced relationship with the buckstay 18. Aswill be explained more fully hereinafter, the tie bar 16, buckstay 18and buckstay bracket 20 and standofi lugs 22 are preassembled at thefactory for assembly at the construction site with the preassembled wallpanels 10 in accordance with the present invention.

Referring especially to FIG. 1, each end of a buckstay 18 has connectedthereto plates 24 projecting beyond the ends thereof and to which links26 are pivotally connected by pins 28. The links 26 are also pivotallyconnected to corner backets 30 by pins 32, in order to allow forexpansion of the wall panel 10 relative to the buckstay 18 and thusavoid any possibility of imposing excessive stresses on theaforementioned tubulous wall and buckstay structure. As best seen inFIG. 4, one end of tie bar 16 extends through a vertically elongatedslot 34 in an enlarged end portion of its adjacent tie bar; and each endof a tie bar 16 is joined as by welding to the corner bracket 30 of theadjacent buckstay assembly at the construction site to complete theperipheral buckstay construction.

Optionally, the outer surface of each wall panel 10 may be provided witha fiat bearing surface for each tie bar 16 by means of filler bars36welded in place between neighboring tubes 12, as shown in FIGS. 5, 6and 7. Preferably the upper and lower ends of the filler bars. 36 arebent inwardly toward the wall panel 10 and a full penetration weld isemployed to join the filler bars 36 to the tubes 12 and the membranebars 13. Filler bars 36 are omitted from the constructions shown inFIGS. 1 to 4.

According to the invention, each wall panel subassernbly includes ahorizontal series of vertically spaced pairs of lugs 38. The upper andlower series of lugs 38 are adapted to receive the tie bar 16 betweenthem; and each pair of lugs is further adapted to receive a locking pin40 in upright position to hold the tie bar 16 in contact with the wallpanel 10. Referring now especially to FIGS.2 and 3, each lug 38 is ofgenerally U-shaped cross section to define a curved bight portion 42intermediate its ends, with its elongated free edge portions joined asby welding to respective neighboring tubes 12 on the outwardly facingsurface of wall panel 10. The bight portion 42 of each lug extendshorizontally and outwardly of the wall panel 10, well beyond the outerextent of the tie bar 16 as determined by its thickness, so that pin. 40is snugly received with little or no clearance between the tie bar 16and the bight portion 42, to thereby connect the tie bar 16 securely tothe wall panel 10. For example, with an L-shaped pin 40 of circularcross section having a diam eter of /8 inch it is advisable for suchclearance to be in the range of between 0 and inch. The. horizontalupper end portion 44 of the pin 40 makes a 90 angle with its mainupright portion so that it serves to limit downward movement of the pin40 by engagement with the uppermost of each pair of lugs 38.

With this arrangement, each tie bar 16 can be preassembled to itsassociated buckstay 18 before shipment to the assembly site; andlikewise the lugs 38 can be preassembled in the shop with each wallpanel 10. Thus, final assembly can be effected by the simple procedureof first fitting each tie bar 16 between the upper and lower rows oflugs 38 and then securing the tie bar in place by manual insertion ofthe pins 40 into the lugs 38 to produce the connection shown in FIGS. 2and 3. With the pin 40 received by the bight portions 42 of the lugs 38,

the tie bar 16 is held against lateral movement between the wall panel10, the lugs 38, and the pin 40 at each location where a connection ismade between the tie bar 16 and the wall panel 10.

One advantage of the present invention is that it minimizes the amountof welding required to make the connection by assembly at theconstruction site under field conditions, and thereby reduces the costsof erecting the vapor generating apparatus. Furthermore, shop-made weldscan be made with greater care and accuracy than welds made at theconstruction site. It will also be noted that the arrangement of thepresent invention leaves the wall free to undergo thermal expansionacross its entire width and height relative to the buckstay assembly,while at the same time providing the furance wall with suitablereinforcement against the pressure forces applied there- I0.

Although the invention has been shown specifically, it will be obviousto those familiar with the art that it is not so limited, but it issusceptable of various changes and modifications without departing fromthe spirit thereof, as covered by the claims which follow.

What is claimed is:

1. In a vapor generator, the combination of:

(a) a furnace including a row of upright tubes joined together to definea wall,

(b) buckstay structure including a horizontally elongated tie bar forreinforcing said wall,

(c) horizontal series of upper and lower lugs each having a bightportion, said lugs being joined to said wall in vertically spaced pairsadapted to receive said tie bar therebetween for contact with said wall,

(d) and elongated locking means adapted for snug reception in uprightposition between the bight portions of each pair of lugs and said tiebar whereby said buckstay structure is assembleable with said wall byfirst positioning said tie bar horizontally between the upper and lowerlugs of said series and next inserting said locking means in said lugstothereby hold said tie bar against lateral movement withoutrestraining'said wall from expansive movement across its width andheight relative to said tie bar.

2. In vapor generating apparatus having a wall comprising a row ofupright tubes joined together in closely spaced relationship andbuckstay structure including a horizontally elongated bar bracing saidwall on the outer surface thereof, that improvement for connecting saidbuckstay structure to said wall at spaced locations along the length ofsaid bar comprising a horizontal series of associated pairs ofvertically spaced lugs connected to said. wall adjacent the upper andlower edges of said bar, and a vertically extending pin for eachassociated pair of lugs adapted to be received thereby in position tohold said bar between said pin, said lugs and said wall.

3. In a vapor generator, the combination of a tubulous wall, anelongated member extending lengthwise across said wall along one sidethereof to reinforce said wall in directions generally perpendicularthereto, a plurality of pairs of lug members connected to said wall atlocations spaced-apart along the length of said reinforcing member, thelug members of each pair being spaced apart in a direction transverse tothe length of said reinforcing member to receive said membertherebetween and to allow substantially free movement of said wallrelative to said reinforcing member in directions parallel to the lengththereof, and, associated with each pair of lug members, a lock memberreceived by both lug members of the pair and supported thereby inextension therebetween for engagement with said reinforcing member toretain said member positioned for abutting contact with said wall toreinforce same.

4. The combination according to claim 3 wherein said lugs each have abight portion projecting outwardly from said wall, and each lock memberis insertably received in the bight portions of its associated lugmembers.

5. The combination according to claim 3 wherein said tubulous wallincludes a plurality of elongated tubes disposed in laterallyspaced-apart parallel relation to one another, and said reinforcingmember extends lengthwise.

in a direction generally perpendicular to the length direction of saidtubes.

6. The combination according to claim 3 wherein said reinforcing memberextends lengthwise in a horizontal direction, and the lug members ofeach pair thereof are disposed in vertically spaced-apart relation toeach other with the lower lug member in each pair being disposed forengagement with the lower portion of said reinforcing member and theupper lug member in each pair being disposed for engagement with theupper portion of said reinforcing member.

7. The combination according to claim 5 wherein said reinforcing memberis a bar of generally rectangular wall and in underlying relation tosaid reinforcing bar 5 for fiat surface bearing contact engagementtherewith.

'8. The combination according to claim 6 wherein the lug members of eachpair thereof are disposed in vertical alignment with each other, and thelock member for each pair of lug members is an L-shaped rod of circularcross section extending at least the full vertical distance from the topof the upper lug member to the bottom of the lower lug member.

9. The combination according to claim 6 wherein nected to the wall attheir leg ends to position the bights defined by the bent portions oftheir U-shapes in outwardly projecting relation to said wall.

References Cited UNITED STATES PATENTS 2,333,777 11/1943 Godshalk 122-63,196,842 7/1965 Huge et a1. 122-235 8/1965 Engelhardt 122-6 FOREIGNPATENTS 1,324,336 3/1963 France.

said lug members are generally U-shaped and are con- 15 CHARLES J MYHRE,Primary Examiner.

1. IN A VAPOR GENERATOR, THE COMBINATION OF: (A) A FURNACE INCLUDING A ROW OF UPRIGHT TUBES JOINED TOGETHER TO DEFINE A WALL, (B) BUCKSTAY STRUCTURE INCLUDING A HORIZONTALLY ELONGATED TIE BAR FOR REINFORCING SAID WALL, (C) HORIZONTAL SERIES OF UPPER AND LOWER LUGS EACH HAVING A BIGHT PORTION, SAID LUGS BEING JOINED TO SAID WALL IN VERTICALLY SPACED PAIRS ADAPTED TO RECEIVE SAID TIE BAR THEREBETWEEN FOR CONTACT WITH SAID WALL, (D) AND ELONGATED LOCKING MEANS ADAPTED FO SNUG RECEPTION IN UPRIGHT POSITION BETWEEN THE BIGHT PORTIONS OF EACH PAIR OF LUGS AND SAID TIE BAR WHEREBY SAID BUCKSTAY STRUCTURE IS ASSEMBLEABLE WITH SAID WALL BY FIRST POSITIONING SAID TIE BAR HORIZONTALLY BETWEEN THE UPPER AND LOWER LUGS OF SAID SERIES AND NEXT INSERTING SAID LOCKING MEANS IN SAID LUGS TO THEREBY HOLD SAID TIE BAR AGAINST LATERAL MOVEMENT WITHOUT RESTRAINING SAID WALL FROM EXPANSIVE MOVEMENT ACROSS ITS WIDTH AND HEIGHT RELATIVE TO SAID TIE BAR. 